Sildenafil as “first line therapy” in pulmonary persistent hypertension of the newborn?

PDE3 inhibition with enoximone as first-line therapy for severe persistent pulmonary hypertension of the newborn during neonatal transport: a case report

Severe Persistent pulmonary hypertension of the newborn (PPHN) can be effectively treated with a PDE3 inhibitor as first‐line treatment during neonatal transport when iNO is not readily available. Starting iNO as soon as possible is strongly advised because of the complementary actions of both therapeutics.

Drug utilisation profile in the neonatal unit of a university hospital: a prospective observational study in Brazil

BACKGROUND

Advances in neonatology have contributed to changes in the drug utilisation profile in neonates, both in the number of drugs and the pharmacotherapeutic groups.

OBJECTIVE

To analyse drug use in the neonatal care unit of a teaching hospital in Brazil and to evaluate the associations among perinatal, clinical care and drug use data.

SETTING

The neonatal care unit of a teaching hospital in Brazil.

METHODS

A prospective observational study was conducted. Perinatal, clinical care and pharmacotherapy data were collected from the patients' medical records. Labelling information regarding neonatal use was analysed for prescribed drugs. The data were analysed using univariate descriptive statistics and quasi-Poisson regression.

MAIN OUTCOME MEASURE

Frequency of drug use by gestational age.

RESULTS

The study included 187 patients; 157 (84.0 %) received drugs. The mean gestational age was 35.8 weeks. The mean number of drugs prescribed per patient was 6.4. The number of drugs used was inversely correlated to gestational age and birth weight. The most commonly prescribed drugs belonged to the following anatomical therapeutic chemical groups: nervous system drugs, anti-infectives for systemic use, and alimentary tract and metabolism drugs. Information regarding neonatal use was given in the labelling of only 20.5 % of the prescribed drugs. Of these, only 9.5 % had information specific for preterm infants.

CONCLUSIONS

Drug administration to neonates is frequently and inversely correlated to gestational age and birth weight. Neonates are exposed to different therapeutic classes, reflecting scientific advances in neonatology. In Brazil, the percentage of drugs with neonate-specific labelling information is low. Consequently, there is an evident need for efforts to guarantee effective and safe pharmacotherapy for neonates.

A randomized, double-blind, placebo-controlled, prospective study of bosentan for the treatment of persistent pulmonary hypertension of the newborn

OBJECTIVE

To assess the efficacy and safety of bosentan as an adjuvant therapy of persistent pulmonary hypertension of the newborn (PPHN).

STUDY DESIGN

Forty-seven neonates with PPHN were randomly assigned to receive either bosentan (n=24) or placebo (n=23). Efficacy was evaluated with a favorable outcome defined as fulfilling all the following criteria (for example, oxygenation index <15, normal pulmonary artery pressure (<20 mm Hg) and no premature discontinuation of the drug because of drug-related toxicity or lack of efficacy). Evaluation of safety was done by monitoring drug-related adverse events.

RESULT

Bosentan treatment was superior to placebo with a favorable response in 87.5% of patients treated with bosentan as compared with 20% of those who received placebo (P<0.0001). None of patients in the bosentan group had drug-related clinical or laboratory adverse events.

CONCLUSION

Bosentan may be a useful adjuvant therapy of PPHN.

Effect of a phosphodiesterase 5 inhibitor on pulmonary and cerebral arteries of newborn piglets with chronic hypoxia-induced pulmonary hypertension

BACKGROUND

The use of phosphodiesterase 5 (PDE5) inhibitors to treat newborns with pulmonary hypertension is increasing. The effect of PDE5 inhibitors on the neonatal cerebral circulation remains unknown. The neonatal piglet model of chronic hypoxia-induced pulmonary hypertension allows the study of the effects of PDE5 inhibitors on both the pulmonary and cerebral circulations.

OBJECTIVES

To determine whether the PDE5 inhibitor, zaprinast, causes dilation in pulmonary and middle cerebral arteries (MCA) of normoxic newborn piglets and those with chronic hypoxia-induced pulmonary hypertension, and to evaluate whether zaprinast alters responses to increased pressure (autoregulatory ability) of the MCA.

METHODS

Two-day-old piglets were raised in normoxia or hypoxia for 3 or 10 days. Pulmonary arteries and MCA were isolated and pressurized, after which changes in diameter to zaprinast were measured. MCA pressure-diameter relationships were determined.

RESULTS

Dilation to zaprinast was similar in pulmonary arteries from normoxic and hypoxic piglets. Zaprinast dilated MCA from all groups but the response was diminished in MCA from piglets raised in hypoxia for 10 days. MCA pressure-diameter relationships (autoregulation) did not differ between the groups.

CONCLUSIONS

Pulmonary artery dilation to zaprinast supports the use of PDE5 inhibitors to treat pulmonary hypertension in neonates. PDE5 inhibitors function as MCA dilators but do not impair the pressure-diameter behavior of the cerebral circulation of either normoxic newborn piglets or those with chronic hypoxia-induced pulmonary hypertension. These findings suggest that cerebral autoregulation is likely to be intact with acute PDE5 inhibitor treatment in infants with pulmonary hypertension in conditions associated with chronic hypoxia.